Direct fired revolving ironer and drier



Nov. 14, 1944. T. J. SULLIVAN DIRECT FIRED REVOLVING IRON'ER AND DRIER Filed Dec Patented Nov. 14, 1944 DIRECT FIRED REVOLVING moNER AND DRIER Timothy J. Sullivan, Butte, Mont, assignor, by mesne assignments, to Red & White Laundry &

Cleaning Company, Butt of Montana Application December 12 e, Mont., a corporation 1942, Serial No. 468,787

" eel-aims. (c1. sis-49) This invention relates"toa revolving'ironer or drier of the drum or cylinder and roll type and more particularly to means for uniformly heating the cylinder.

The controlled and uniform heating of .the

- surface of the cylinder of a cylinder and roll ironer presents a serious problem. Somevery complicated and expensive devices and arrangements have been proposed to accomplish this highly important result. I a

1 One of the simplest means for heating the cylinder ofa cylinder and roll ironeris a gas flame insi'de the hollow cylinder, .but' this results in I extremelynon-uniform heating." Many of the proposals have been designed to overcome the defects of this simple means.

It will be appreciated .that both hot spotsythat is, areas which mayfscorchor burn the 'fabric being ironed, as well aS'ICQld spots whichwill not sufficiently heat the fabriciare .to be avoided.

'For bestresults it'is. not. s'uficient merely to avoid hot spots which will. burn and cold spots whichwill notiron'or' drythe fabric but even relatively hot and cold spots-should be avoided. The heat should be supplied in such a :Waythat the temperatureof an area of the cylinder from which heat is abstracted relativelyrapidly due to unevendistribution of the damp cloth on the surface of the cylinder will be quicklybrought back-to or maintained atsubstantiallythe sainetemperature as other areas from whichmuch less heat is abstracted in the ironing operation. "One way to accomplish this result-is by contacting the inner 'surface of the cylinder wall with a relatively'large volume of heatingfluid at a uniform temperaturewhich is not materially above the desired temperature of the ironing surfaceof the cylinder.

In this way -a large amount'of heat may be supplied to. areas that needit'while avoiding the possibility of overheating other areas.

The proposals for effecting a uniform heating combustion gas is directed toward the inner wall of thecylinder. the provision of a stationary cen-., tral imperforate tube within the cylinder through which flame and hot combustion gas passes to one end of the cylinder andthen back along the cylinder wall, and'the provision of a water .or steam jacket in contact with the inner wall of the cylin-.

der, and means for heating the fluid in the jacket or forsupplying hot fluid to the jacket.

The present invention represents a considerable simplification as compared with the prior proposals and at the same time provides a highly uniform heating of the cylinder which is controllable to a high degree tomaintain or vary at will the operating temperature of the cylinder.

The invention, in its simplest "embodiment, comprises a hollow cylinder provided with a central imperforate tube having a gas burner at one end and open at the other end within the cylinder to permit the hot gas to flow from the burner through the inner tube, to the open end thereof and then back between the cylinder and tube to an outlet. Th invention is characterized by its extreme simplicity compared to its efllcient operation and its freedom from parts which may wear out and require replacement or fail to function efficiently.

The invention is embodied in a single cylinder ironer' illustrated in Figs. 1' and 2 and in a double cylinder ironer illustrated in Figs. 3 and 4; in thelatter of which one cylinder is like the singlecyh inder of the ironer illustrated in Figs. 1 and 2 and the other cylinder is a simple hollow cylinder, without anycentral tube, through which the hot ga's'from the first cylinder passes.

In the drawing: a Fig. 1 Ba vertical section through the axis of the cylinder of asingle cylinder ironer;

Fig. 2 is a right end elevation of the ironer oi Fig. 1, Y

Fig. 3'is a section on a plane through the axes of the cylinders of a two cylinder ironer, and

Fig. 4 is a left end elevation of the ironer of Fig.3. Referring to Figs. 1 and 2, l is the main ironing cylinder mounted on trunnions 2 and 3 can .rie'd by bearing blocks 4 and 5- supported by the legs 6 and l. illustration of conventional means for rotating the cylinder is omitted in order to simplify the showing of the invention. Small rolls 8 are mounted on a supporting structure- (not shown) to cooperate with cylinder l. Within the cylinder l is the cylindrical tube 9 axially supported therein by the arms ID. The tube 9 extends to the right end of the cylinder as it appears in Fig.- 1 and communicates with the hol- The other end of the tube 9 stops short of the other end of the cylinder I, leavingthe space H between the closed end of cylinder! and. the end of the tube 9. A stationary housing I2 is fitted around the trunnion 3 and against the end of cylinder I, with a slid ing contact, to receive the used heating gas (products of combustion) and convey it to the flue I3. The gas burner I I is carried on the end of the pipe I5 which extends through the hollow trunnion 3 and positions the burner in the end of the tube 9. Pipe I5 connects with a transverse pipe I6 supported by brackets H which in turn are supported by the bearing 5.

Pipe I6 connects to the mixer I8 which comprises two valves I9 and 29 for controlling the sup-; plies of air and gas (not shown) and these valves are electrically controlled to increase or decrease the amount thereof and consequently the size of the flame delivered by the burner I5 in response to the action of the thermostat 2I which is in heat transfer relationship to the gas passing through the flue I3.

In operation, the cylinder I is rotated, burner I l started and the thermostat 2| set for the de'- sired temperature. The tube 9 protects the wall of cylinder I against contact with the extremely hot gas of the flame issuing from the burner I4 and prevents any irregular heating of the surface of the cylinder by the flame. By the time the products of combustion produced by the burner I4, mixed, if desired, with air admitted through the trunnion 3, reach the opposite end of the tube 9 they have become thoroughly mixed and pass through the chamber II and back between the tube 9 and cylinder I to the casing I2 and flue I3. The temperature of the products of combustion or their mixture with air admitted through trunnion 3 may be regulated by regulating the size of the flame or the admission of air or both so that the temperature of the gas mixture in the chamber II is not sufficiently higher than the desired temperature of the cylinder to give rise to uneven heating of the cylinder. The hot gas passes fairly uniformly around the tube 9 and there is ordinarily, in conventional apparatus in which the space between tube 9 and cylinder I is not too great, suflicient turbulence to keep it uniformly mixed and prevent any unequal heating of the cylinder circumferentially. The rotation of the cylinder, of course, favors uniform heating. There is very little temperature difference between the ends of the cylinder which might be expected as a result of the fact that the heating gas is being cooled as it passes from the chamber II to the housing I2. This may be explained by the fact that the gas passes fairly rapidly and carries a large surplus of heat so that its temperature does not drop materially and further by the fact that the tube 9 is definitely hotter at the end adjacent the burner than at the other end, and by transferring more heat to the gas in the reg'ion adjacent the burner than at the opposite end of the cylinder tends to maintain it at a uniform temperature. Regardless of the cause, it is a fact that the cylinder I is heated quite uniformly around its circumference and from end to end.

Referring. to Figs. 3 and 4, it will be seen that the lower cylinder is identical with the single cylinder I of Fig. 1 but the housing 22 instead of leading to a flue delivers the gas to the second cylinder 23. Cylinder 23, like cylinder I, is carried by trunnions 24 and 25 supported by the legs or frame 26 and is rotated by conventional means (not shown). Cylinder 23, however, has no central tube like tube 9 of cylinder I and the hot gas simply passes through it and to the housing 21 a'n'd'flue 28. The thermostat 2| is in the housing 22. In this modification, illustrated in Figs. 3 and 4, the rollers 29 cooperating with cylinder I are located around the lower side of it and rollers 39 cooperating with cylinder 23 are located around its upper side. Cylinder 23 is connected to its trunnions 24 and 25 through the arms 3I and 32.

In the operation of the double ironer of Figs. 3 and 4, the hot combustion gas from the burner I4 which operates under the control of the adjustable thermostat 2| located in heat transfer relationship to the gas passing from cylinder I to cylinder 23 passes through the central tube '9, through the chamber II, between the tube 9 and the cylinder I, through the housing 22 and through cylinder 23 to the housing 21 and flue 28, resulting in a uniform heating of both cylinders.

The natural draft created by the flue is sufficient to prevent objectionable leakage of gas into the atmosphere surrounding the ironer through the joint or joints between the rotating cylinder or cylinders and the stationary housings I2, 22 and 21. This draft is suflicient to obviate any need of other means such as a fan, for moving the gas. Moreover, as stated above, with the type of burner illustrated, i. e. one which produces a flame which is relatively small in diameter compared to the size of its enclosure (the tube 9) and which does not impinge against the wall of tube 9, the heating of the cylinder I is highly uniform and there is no need of other measures or means, other than the admission of air through the trunnion 3, for regulating the temperature of the gas to secure uniform heating. In the two cylinder ironer of Figs. 3 and 4, the second cylinder 23 is uniformly heated because the gas which heats it is at a uniform temperature only slightly above the desired temperature of the 'cylinder as a result of its passage through tube 9 and the space between tube 9 and cylinder I.

There may be a slight temperature difference between the two ends of cylinder 23 due to the cooling of the gas as it passes through it, but this difference is not suflicient to produce a noticeable difference in the ironing results in normal operation of the ironer.

The essence of the invention, as previously indicated, is its extreme simplicity and freedom from operating parts which may give rise to difliculties or shorten the life of the ironer. Features of the ironer which contribute to its success are the shape and size and direction of the burner flame with respect to the size of the tube 9, the provision for a free flow of the combustion gas with air drawn in through the trunnion 3, through the tube 9, the ample openings between the arms II], the ample chamber I I and the space between tube 9 and cylinder I. It will be appreciated that considerable variation in the size of the ironer and in the relative sizes of the parts is permissible so long as the general plan, as illus-v cylinder axially supported therein'by spaced rainder being closed at one end and one end of said tube being open and terminating short of said closed end of the cylinder to provide a chamber through which said tube communicates withthe space between the tube and the cylinder, a flame producing burner positioned axially adjacent the other end of the tube, said burner being adapted to produce a flame which is small in diameter relative to the diameter of the tube and extends axially of said tube, a hollow trunnion supporting the end of the cylinder opposite said closed end' an ironing surface, means for rotatably supporting said first cylinder comprising a. hollow trunnion at one end thereof the diameter of which is smaller than that of said cylinder, a tube the diameter of which is smaller than that of said dial arms and having one end in communication with the outer atmosphere through said hollow trunnion, the other end of said first cylinder being closed, and the other end of said tube terminating short of the closed end of the cylinder,

"a fuel burner positioned in the end of the tube adjacent said hollow trunnion and adapted to project a flame which is small in diameter relative to the diameter of the tube axially of said tube and toward the opposite end thereof, a housing surrounding said hollow trunnion and enclosing the remainder of the adjacent end of said first cylinder, a second rotatably mounted cylinder the outer surface of which provides an v ironing surface, said second cylinder being open at both ends, and a housing enclosing one end of said second cylinder and communicating with said housing enclosing an end of the first cylinder. I

TIMOTHY J. SULLIVAN. 

